The present invention relates to a limb stump receiving sleeve comprising an integratable or integrated receptacle for a sealing element, by means of which a limb stump is locked in a stump receiving sleeve by sealing the distal region of the interior of the stump receiving sleeve with respect to the limb stump and the surrounding atmosphere.
When connecting a patient's stump to a limb stump receiving sleeve, the stump, which is covered by a liner, is usually inserted and fixed from above, in the direction of the closed, distal end of the stump receiving sleeve.
The stump is fixed by a negative pressure produced in the limb stump receiving sleeve when inserting the stump, and for this purpose numerous stump receiving sleeves have a valve close to their distal end, via which the compressed air can escape from the sleeve during insertion of the stump.
In many embodiments, the liner is sealed with respect to the receiving sleeve only by sealing resulting from planar bearing contact between these two parts themselves, and the sealing is dependent on the materials used and the dimensioning of the liner and of the interior of the stump receiving sleeve. If the external diameter of the liner at least corresponds to the internal diameter of the shaft, negative pressure can be produced permanently in the shaft via this form of the planar seal. If the external diameter of the limb stump, including the liner, is greater than the internal diameter of the shaft, however, the resultant pressure on the shaft will feel unpleasant, or it will be harder to fit into the prosthesis. Since fluctuations in stump volume can be observed in most prosthesis wearers, the resultant fit between the receiving sleeve and the liner varies.
Furthermore, when the stump is moved, i.e. when walking, a gap may briefly appear between the stump and the inner side of the receiving sleeve, through which gap the internal pressure escapes and the fit of the stump in the receiving sleeve is impaired. This is all the more so if, owing to a desired wearing comfort, the fit of the stump with respect to the receiving sleeve is no longer so pronounced. This often results in the stump sliding out of the stump receiving sleeve when the limb is lifted.
In order to solve this problem, EP 0 631 765 B1 proposes a stump receiving device into which a sealing element is inserted, said sealing element having a virtually circular design and having an opening in the center, through which the stump is inserted into the receiving sleeve. A seal is thereby continuously provided, even when the stump is moved, in the receptacle between said sealing membrane and the liner or stump itself.
The sealing element described is circumferentially provided with a ring which engages into a groove made in the stump receiving sleeve, where it is fixed.
These embodiments have the disadvantage that firstly the sealing in the groove, into which the ring of the sealing element engages, is problematic or can only be implemented with a high level of expenditure, and secondly the positive locking of the ring in the groove is often insufficient.
When fitting the stump into or removing it from the stump receiving sleeve, the circumferential ring is often pulled out of the groove, as a result of which naturally either the function is not performed or the sealing element has to be laboriously fitted back in. Furthermore, it is very complicated to implement the circumferential groove such that it is formed in a positively locking manner and free from bubbles on the inner side of the limb stump receiving sleeve.